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971.
Thomas Gerstner Markus Holtz Ralf Goschnick 《Insurance: Mathematics and Economics》2008,42(2):704-716
New regulations and a stronger competition have increased the importance of stochastic asset-liability management (ALM) models for insurance companies in recent years. In this paper, we propose a discrete time ALM model for the simulation of simplified balance sheets of life insurance products. The model incorporates the most important life insurance product characteristics, the surrender of contracts, a reserve-dependent bonus declaration, a dynamic asset allocation and a two-factor stochastic capital market. All terms arising in the model can be calculated recursively which allows an easy implementation and efficient simulation. Furthermore, the model is designed to have a modular organization which permits straightforward modifications and extensions to handle specific requirements. In a sensitivity analysis for sample portfolios and parameters, we investigate the impact of the most important product and management parameters on the risk exposure of the insurance company and show that the model captures the main behaviour patterns of the balance sheet development of life insurance products. 相似文献
972.
973.
Markus Lau Stefan Lbus Ralf Courths Samed Halilov Herbert Gollisch Roland Feder 《Annalen der Physik》1993,505(5):450-464
High-resolution normal photoemission (ARPE) spectra have been recorded for Cu3Au(111) with the use of polarized synchrotron and rare-gas resonance radiation in the photon energy range from 9 to 27 eV. It is for the first time that dispersions of the gold-like bands have been found experimentally. Using a fully relativistic layer-KKR photoemission formalism, occupied and unoccupied bands as well as one-step-model photoemission spectra have been calculated. The comparison of calculated spectra with experimental ones and the observation of direct-transition resonances upon photon energy near the Brillouin zone-center reveal a shift of the unoccupied ground-state bands by about +2.5 eV (self-energy shift). The direct-transition structures in the experimental spectra have been exploited to determine the dispersions of the occupied bands along the [111] direction (A line in k space). In order to determine the wave vector of the experimental direct transitions we used as final state that calculated unoccupied band along [111], which also exists in pure copper and gold up to about 20 eV above the Fermi energy (“unfolded” band structure), shifted by + 2.5 eV. The experimental occupied bands with Cu character are in very good agreement with theory after shifting the latter by about 0.3 eV to lower energy, whereas somewhat bigger discrepancies exist for the gold-like bands. 相似文献
974.
Various procedures of coarse graining in quantum mechanics and their relationships are reviewed. A recently developed notion of relative coarse graining is described which is based on a certain type of classical embedding of quantum states. The ensuing structure of the set of quantum observables is studied. As an application of the new concept an operational classical limit procedure is sketched out. 相似文献
975.
Henna Elfström Markku Kuittinen Bernd H. Kleemann Ralf Arnold 《Optics Communications》2006,266(2):697-703
Area-coded effective medium structures (ACES) are a recently presented novel type of diffractive structure. Because of their higher stability compared to 2D binary blazed gratings, they have the potential of a broader use in micro-optics applications. The first fabrication with electron-beam lithography validate the theoretical model of blazed ACES. The measured diffraction efficiencies are in very good agreement with the values obtained from rigorous electromagnetic analysis. 相似文献
976.
Heike Siebert 《Journal d'Analyse Mathématique》2006,98(1):145-168
LetF be a family of mappingsK-quasiregular in some domainG. We show that if for eachf∈F, there existsk>1 such that thek-th iteratef
k
off has no fixed point, thenF is normal. Moreover, we examine to what extent this result holds if we consider only repelling fixed points, rather than
fixed points in general. We also prove thatF is quasinormal, ifF contains only quasiregular mappings that do not have periodic points of some period greater than one inG. This implies that a quasiregular mappingf:ℝ
n
with an essential singularity in ∞ has infinitely many periodic points of any period greater than one. These results generalize
results of M. Essén, S. Wu, D. Bargmann and W. Bergweiler for holomorphic functions. 相似文献
977.
Alfred V. Hirner Jrg Feldmann Reiner Goguel Spyridon Rapsomanikis Ralf Fischer Meinrat O. Andreae 《应用有机金属化学》1994,8(1):65-69
We have detected volatile species of silicon, vanadium, arsenic, bromine, tin, antimony, tellurium, iodine, mercury, lead and bismuth in gases released from domestic waste deposits, using inductively coupled argon plasma mass spectrometry (ICP MS). By concurrent aspiration of a multielement standard solution for calibration, the element concentrations in deposit gas are found to be in the range from 0.1 ng m?3 to 10 μg m?3 gas. The global amount of some metal species emitted by this process may be of the order of several tons per year. These results suggest a biogeochemical pathway for the transfer of metals into the atmosphere via volatile species. This process may have significant influence on atmospheric cycling of metals as well as on metal toxicity within ecosystems. 相似文献
978.
We report the first Mössbauer spectra of a metallic glass obtained above the glass transition temperature (T G ). The temperature at which both the Lamb-Mössbauer factor and the average quadrupole splitting decrease sharply is in agreement withT G determined by thermal and mechanical measurements, but the width of the quadrupole splitting distribution starts to increase at a much lower temperature. These results are compared with data from similar measurements on more conventional glasses. 相似文献
979.
We provide a short proof of the well-known fact that a division ring of finite degree over its center that admits an anti-automorphism of the first kind, i.e., an anti-automorphism that fixes the center elementwise, also admits an involutive anti-automorphism.
980.
Ralf Ludwig 《Chemphyschem》2005,6(7):1369-1375
A combination of density functional calculations of molecular clusters with a quantum cluster equilibrium (QCE) model provides evidence that liquid methanol is dominated by cyclic and/or lasso structures. Only cluster populations including these structures fit the measured thermodynamic and spectroscopic properties, such as heat of vaporization, heat capacity, NMR chemical shifts, and quadrupole coupling constants. On the other hand, cluster populations comprising open-chain structures fail to reach the experimental values: the heat of vaporization is about 10 kJ mol(-1) too low, and the proton chemical shift is insufficiently downfield-shifted by about 1 ppm. 相似文献